1. Field of the Invention:
The present invention relates generally to the field of conveying machines used in mines and, more specifically, to flexible mobile conveyor systems.
2. Description of the Related Art:
Mobile conveyor systems are known in the mining field to include a series of interconnected and articulated conveyors, or continuous flexible conveyors supported by a series of interconnected and articulated support vehicles. It is desirable that such conveyors are relatively long and highly flexible in all, horizontal, vertical and transverse planes, and capable of relatively accurate tracking within confined spaces of the mines, while simultaneously conveying bulk material.
For example, U.S. Pat. No. 3,863,752 to Sibley discloses a plurality of carriage units which are connected to facilitate end-to-end articulated movement, while supporting an endless conveyor along substantially the full length of the interconnected carriages.
U.S. Pat. No. 4,256,213 to Shaw et al. discloses a mobile chain conveyor having plurality of connected carriages which are operative to track each other during traversing of a mine floor surface. Each carriage has driven support wheels intermediate its length and supports an endless chain conveyor and associated drive means.
U.S. Pat. No. 4,951,801 to Mraz discloses a mobile conveyor apparatus comprising a plurality of pivotally interconnected modular carriages each of which has a pair of transversely aligned support wheels intermediate its longitudinal length so as to track behind the wheels of the preceding carriage, and support an endless belt conveyor including belt guidance means and belt drive means.
In the aforementioned Shaw et al. and Mraz patents, a relatively accurate tracking of carriages behind one another is achieved by transversely aligned support wheels intermediate the length of each carriage. The position of wheel supports intermediate the length of modular carriages Limits their length, as the use of longer vehicles makes the train less stable, especially where the floor in uneven, which is normal in mines.
Other flexible mobile conveyors currently in the use employ mobile supports proximal to the ends of modular conveyors or carriages, which leads to incorrect tracking of such train and requires either a manual steering of each mobile support or an exceedingly complex computerized system of sensors and actuators having an insufficient accuracy of tracking.
It would be highly desirable in a flexible mobile conveyor to position the mobile supports at or in proximity to the ends of individual modular conveyors or carriages and provide a mechanical linkage which would automatically assure an accurate tracking of such mobile supports one being the other.